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Effect, of quantization

When an electromagnetic wave interacts with resonators, the effect of quantization of all possible stationary stable oscillating amplitudes arises without the requirement of any specifically organized conditions (like the inhomogeneous action of external harmonic force). [Pg.112]

The greater the size of the system, the less important are the effects of quantization. [Pg.327]

Up to this point we have treated the electrons as a set of classical charge carriers, except for the confinement in the z direction which introduces quantization of the motion along z, and localization in the xy plane. Now we introduce the effects of quantization in the remaining two dimensions. The behavior of electrons in the plane exhibits quantization in two ways, which are actually related (see Problem 4). Here we give only a qualitative discussion of these two levels of quantization. [Pg.270]

A-to-D noise is the effect of quantization on reported noise it is discussed with Test Equipment (see Section 10.2.3). [Pg.129]

The theoretical effect of quantization by the ADC is discussed in Section 10.2.3. Above about 1 count, the ADC adds (in quadrature) the square root of 1/12 count (about 0.28 count). Below about 0.5 count, the ADC can yield any value between zero and 0.5 count. Typically, the actual noise added by the ADC should be on the order of less than 0.5 count (in quadrature), and the ADC resolution is typically selected so that the noise inherent in the signal chain is equal to about 2 ADC counts. [Pg.208]

Figure A3.8.3 Quantum activation free energy curves calculated for the model A-H-A proton transfer reaction described 45. The frill line is for the classical limit of the proton transfer solute in isolation, while the other curves are for different fully quantized cases. The rigid curves were calculated by keeping the A-A distance fixed. An important feature here is the direct effect of the solvent activation process on both the solvated rigid and flexible solute curves. Another feature is the effect of a fluctuating A-A distance which both lowers the activation free energy and reduces the influence of the solvent. The latter feature enliances the rate by a factor of 20 over the rigid case. Figure A3.8.3 Quantum activation free energy curves calculated for the model A-H-A proton transfer reaction described 45. The frill line is for the classical limit of the proton transfer solute in isolation, while the other curves are for different fully quantized cases. The rigid curves were calculated by keeping the A-A distance fixed. An important feature here is the direct effect of the solvent activation process on both the solvated rigid and flexible solute curves. Another feature is the effect of a fluctuating A-A distance which both lowers the activation free energy and reduces the influence of the solvent. The latter feature enliances the rate by a factor of 20 over the rigid case.
An effect of space quantization of orbital angular momentum may be observed if a magnetic field is introduced along what we now identify as the z axis. The orbital angular momentum vector P, of magnitude Pi, may take up only certain orientations such that the component (Pi) along the z axis is given by... [Pg.17]

For example, the measured pressure exerted by an enclosed gas can be thought of as a time-averaged manifestation of the individual molecules random motions. When one considers an individual molecule, however, statistical thermodynamics would propose its random motion or pressure could be quite different from that measured by even the most sensitive gauge which acts to average a distribution of individual molecule pressures. The particulate nature of matter is fundamental to statistical thermodynamics as opposed to classical thermodynamics, which assumes matter is continuous. Further, these elementary particles and their complex substmctures exhibit wave properties even though intra- and interparticle energy transfers are quantized, ie, not continuous. Statistical thermodynamics holds that the impression of continuity of properties, and even the soHdity of matter is an effect of scale. [Pg.248]

Anomeric effect of monosaccharides and their derivatives insights from the new QVBMM (quantized valence bond molecular mechanisms) molecular mechanics force field 98H(48)2389. [Pg.206]

In the above discussion it has been assumed that the type of quantization has not been changed, and that 5 and p eigenfunctions retain their identity. This is probably true for H20 and H202, and perhaps for NH3 and As44 also. A discussion of the effect of change of quantization on bond angles is given in a later section. [Pg.70]

The Structures of Simple Molecules.—The foregoing considerations throw some light on the structure of very simple molecules in the normal and lower excited states, but they do not permit such a complete and accurate discussion of these questions as for more complicated molecules, because of the difficulty of taking into consideration the effect of several unshared and sometimes unpaired electrons. Often the bond energy is not great enough to destroy s-p quantization, and the interaction between a bond and unshared electrons is more important than between a bond and other shared electrons because of the absence of the effect of concentration of the eigenfunctions. [Pg.81]

The calculated energy of interaction of an atomic moment and the Weiss field (0.26 uncoupled conduction electrons per atom) for magnetic saturation is 0.135 ev, or 3070 cal. mole-1. According to the Weiss theory the Curie temperature is equal to this energy of interaction divided by 3k, where k is Boltzmann s constant. The effect of spatial quantization of the atomic moment, with spin quantum number S, is to introduce the factor (S + 1)/S that is, the Curie temperature is equal to nt S + l)/3Sk. For iron, with 5 = 1, the predicted value for the Curie constant is 1350°K, in rough agreement with the experimental value, 1043°K. [Pg.762]

Horlick, G., Reduction of Quantization Effects by Time Averaging with Added Random Noise, Anal. Chem. 47, 1975, 352-354. [Pg.405]

QC. The effect of an increase in fundamental bandgap due to size quantization is not specific to silicon, but common to all semiconductors [He2, Br3, Wei]. [Pg.151]

Commonly encountered cubic equations of state are classical, and, of themselves, cannot rationalize IE s on PVT properties. Even so, the physical properties of iso-topomers are nearly the same, and it is likely in some sense they are in corresponding state when their reduced thermodynamic variables are the same that is the point explored in this chapter. By assuming that isotopomers are described by EOS s of identical form, the calculation of PVT isotope effects (i.e. the contribution of quantization) is reduced to a knowledge of critical property IE s (or for an extended EOS, to critical property IE s plus the acentric factor IE). One finds molar density IE s to be well described in terms of the critical property IE s alone (even though proper description of the parent molar densities themselves is impossible without the use of the acentric factor or equivalent), but rationalization of VPIE s requires the introduction of an IE on the acentric factor. [Pg.414]

Use the Internet to investigate the phenomena known as blackbody radiation and the photoelectric effect. Write a brief report outlining the nature of these phenomena, why nineteenth-century physics could not explain them, and how the new idea of quantization could. Go to the web site above. Click on Web Links to find out where to go next. [Pg.126]

There are two effects of the anharmonicity of the quantized energy levels described above, which have signiflcance for NIRS. First, the gap between adjacent energy levels is no longer constant, as it was in the simple harmonic case. The energy levels converge as n increases. Second, the rigorous selection rule that An = +1 is relaxed, so that weak absorptions can occur with n = 2 (flrst overtone band), or +3 (second overtone band), etc. [Pg.113]

Finally, let us consider the effect of applying an external magnetic field B (Kartsovnik, 2004). In a magnetic field, the motion of quasi-particles becomes partially quantized according to the expression ... [Pg.81]

Optical absorption spectroscopy is often carried out on CD films to verify that the films have a bandgap expected from the deposited semiconductor. Additionally, since CD films are often nanocrystaUine and the most apparent effect of very small crystal size is the increasing bandgap due to size quantization (the effect is visible to the eye if the bandgap is in the visible region of the spectrum), absorption (or transmission) optical spectroscopy is clearly a fast and simple pointer to crystal size, since bandgap-size correlations have been made for a number of semiconductor colloids and films. [Pg.38]


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See also in sourсe #XX -- [ Pg.243 ]




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